Our technique of 'training' the roulade here (see additional information) is a neat little trick, if you don't know it already. Once you've cracked it (or not, in the case of your sponge), you'll feel like a roulade-making pro.
For the roulade:
- 70 grams shelled pistachios kernels, plus an extra 15g, roughly chopped
- 4 large eggs (whites and yolks separated)
- 130 grams caster sugar
- 2 tablespoons hot water
- 80 grams self-raising flour
- ⅛ teaspoon salt
- ⅛ teaspoon almond extract
- 20 grams icing sugar
- 300 grams fresh raspberries
For the white chocolate cream:
- 200 grams white chocolate buttons (or 200g block of white cooking chocolate, roughly chopped into 1cm pieces)
- 75 grams unsalted butter (soft but not oily)
- 280 grams cream cheese
- 270 millilitres double cream
- ⅛ teaspoon almond extract
Pistachio Roulade with Raspberries and White Chocolate is a guest recipe by Yotam Ottolenghi and Helen Goh so we are not able to answer questions regarding this recipe
- Preheat oven to 200°C /180°C fan/ Gas mark 6. Grease a 35 x 30cm shallow baking tray and line with baking parchment.
- Place 70g of pistachios in the small bowl of a food processor (or use a spice grinder) and grind until fine but not oily: don't worry if there are some medium-sized pieces in the mix, these will not affect the cake. Set aside until needed.
- Place the egg yolks and sugar in the bowl of an electric mixer with the whisk attachment in place. Mix for about 4 minutes, until thick and creamy. Transfer the mixture to a large bowl and add the hot water, dribbling it down the sides of the bowl. Sprinkle over the ground pistachios and gently fold to combine: don’t worry if it's not well mixed at this stage.
- Sift the flour and salt together into a bowl, then sift again into the egg yolk and pistachio mixture. Fold to combine.
- Beat the egg whites in a clean bowl of an electric mixer with the whisk attachment in place. Whisk to form soft peaks, then fold into the pistachio mix, a third at a time, along with the almond extract. Scrape the batter into the tray and bake for 15-18 minutes, or until the cake springs back when lightly touched in the centre. Remove the cake from the oven and set aside for 5 minutes.
- Sift half the icing sugar evenly over the surface of the cake and cover with a clean tea towel. Place a wire rack on top, then flip the cake over, so that the wire rack is now underneath the tea towel and cake. Lift off the tray, carefully peel away the paper and lightly dust the top of the cake with the remaining icing sugar.
- With one of the short ends of the sponge facing towards you, roll up the still-warm cake with the tea towel inside. Allow the cake to rest for 10 minutes, still rolled up in the tea towel (this 'trains' the cake for the final roll), then unroll the cake and set aside to come to room temperature. Don't worry if the ends of the cake curl up a little or if the surface has some cracks in it: this often happens.
- Make the chocolate cream while the cake is cooling. Place the chocolate in a bowl set over a pan of simmering water, making sure the base of the bowl is not touching the water. Stir from time to time until melted, then remove from the heat and set aside to cool slightly. Place the butter in the bowl of an electric mixer with the paddle attachment in place. Beat on a medium-high speed for 30 seconds, until smooth, then add the cream cheese. Beat well to combine, then add the melted chocolate. Continue to beat until smooth before adding the double cream and almond extract. Beat on a medium-high speed until the mixture forms soft waves.
- When ready to assemble, use a small spatula to spread about two-thirds of the white chocolate cream evenly over the surface of the cake. Leave a border of about 2cm without any cream at the short end of the cake furtherest away from you. Place all but twelve of the raspberries evenly on top of the cream, then roll the cake up as you did before, this time without the tea towel inside. Using a long spatula or fish slice, transfer the cake to a long platter. Use a small spatula or butter knife to spread the remaining cream all over the cake, smoothing it out as you go. Place the remaining raspberries along the centre of the cake, and sprinkle with the extra pistachio nuts.
The white chocolate cream can be prepared a day in advance and kept in the fridge; remove it from the fridge about 30 minutes before you want to use it, so that it softens up a little.
Once assembled, the cake is best eaten on the same day, although any leftovers will keep in the fridge for up to a day. Allow it to rest at room temperature for 30 minutes before serving.
In order to prepare our roulade before it's rolled, we like to 'train' it. This is done by rolling it in a clean, dry tea towel after it's been baked so that it rolls seamlessly (and without breaking) once the cream filling is in place. It's a neat trick.